Yeah, clarification is needed. My take is that he means that most people that visit OpenMW aren't here to contribute to the codebase, so why would they fork us? But the repo doesn't really "need" stars, it needs contributors

I would be in favor of this. Stars indicate that people—including non-developers—appreciate the project, even if they aren't interested in or aren't able to contribute. Forking is something that only developers who have the time and ability to contribute the codebase would do.

Anybody who wants to contribute will make a fork regardless of if the metric says "Star on GitHub" or "Fork on GitHub". But for a casual fan who wants to show their appreciation, stars are a better metric.

I have never forked a GitHub project because the website asked me to. But I have starred a project because the website asked me to. And for non-developers, starring is much more reasonable to ask than forking (yes, they could make a meaningless fork to show their appreciation, but that's exactly what the purpose of stars is).